Analysis on power flow of distribution network with DGs

Distributed generations are used more widely, so the problems of grid-connected become obvious. Power flow is the basic of studying power energy and the grid stability. This paper talks about the math model of distribution generations in power flow calculation based on different type. Then it introduces characteristics of classic distributed grid. Some power flow algorithms with DGs that applied wildly at present is expounded in details. It puts forward to advantages and shortcomings of each algorithm. The algorithm of solving PV nodes in back/forward sweep calculation is improved which is based on the power flow algorithm. The current value can be directly got by the amount of voltage change, and it doesn´t need update reactive flow. The admittance matrix is derived that adapt small load and accurately handle the power flow in small load with DGs.